Normally after the first four days of F1 testing at Barcelona, we have a good idea of who is doing well, who is in trouble and the general running order. This year over the four days, we’ve had rain, extreme cold, SNOW! and even a little dry running. With less than two days mileage from the four days, its hard to garner any solid feel of where everybody stands. What little running happened was on tyres unsuited to the cold conditions and instead time were given over to non-performance testing, such as aero runs.
However, we do have some observations on updates to the cars, either new parts, parts not seen on the launch images or parts ‘hidden’ on the launch cars. So here is the EVERYTHING TECHNICAL run down on what’s been seen on each car through the first test.
As usual the Mercedes went straight out on long runs on the first day, racking up mileage with a car identical in specification to that launched at Silverstone the week before. Again, it appears that the Mercedes W09 is running a lot of 2017 spec bodywork, the expectation being that the second test or Melbourne will see something more definitive appear for this season.
Some smaller details new on the car emerged, a small fin on the front brake duct. Bodywork rules are relatively free for the ‘brake ducts’ inboard of the front wheel, there’s a 120mm width for any bodywork to be added, that doesn’t have to justify itself as brake cooling, nor as it turns with the steering does it have to meet that aspect of the immovable aero rules. Thus, Mercedes little fin is legal and largely innocuous, later in the test the team ran with dense foam bonded to the duct near to the new fin, to ensure nothing is flexing and contacting the tyre.
Much of the testing was completed with a curved rear wing, plus the wide T-wing seen on the first day. A straighter higher downforce\drag rear wing was also tried. But the key novelty was a new front wing, the outer section being made yet more complex!
In normal race car terms, the outer section of the wing called the endplate, it’s there to seal the top and bottom of the wing to preserve the pressure difference and therefore the downforce. In modern F1, this is a functional requirement of the endplate, but the shaping of much of the outer span of the front wing is now used to turn the airflow around the front tyre. This having the downstream effect of keeping the spinning tyre’s turbulence away from the rear bodywork. So, we saw this updated wing with even more aerofoil sections in front of the tyre and the vertical endplate vane shortened, with a large twisted section added-in to further turn the airflow outwards. Mercedes are the de facto team for extremely complex aero, cutting up surfaces into multiple edges for creating vortices to control the airflow. So, the new updates are not surprising and shows how much sophisticated the bodywork on an F1 car can get.
Mercedes ended up fastest through the test with the second highest mileage, combined with outwardly trouble-free running, this is ominous for 2018
Along the same lines as Mercedes, Ferrari ran its launch spec car and throughout the week and clocked lots of trouble-free miles. Rules for pitlane routines and security are different for testing than for Races. Ferrari were allowed to bring the car into the pitlane and stop behind screens to keep the SF71H from prying eyes and long lenses. This practice was eased once the crowds of the first days subsided, but still the volume of team members simply stepping in front of photographers was common practice and arguably another unsafe for a live pitlane.
Through out the test other teams focused on aero runs, fitting the car with sensor arrays and oil-streak flow-viz paint. Ferrari were not following this practice, running the car without lots of obvious add-on sensors and simply completing longer stints. Albeit some stints included fixed speed runs along the straight, with the cars normal onboard telemetry able to measures loads and pressures from the aero surfaces.
In design terms nothing new stood out on the Ferrari, the internal ‘winged’ mirrors (LINK) were open for more scrutiny and the air ducted in from the frontal slots exiting above and below the mirror glass, but not to the side. While far from certain, the initial hypothesis that the mirrors are downwash generators, pushing the airflow down towards the sidepods still seems the most feasible. While the mirror position may not allow the wake from the mirror to go directly down into the upper sidepod inlet, they certainly contribute to flow going into the cooling duct and helping airflow attach to the flat sidepod surface behind the inlet.
Last season the 2017-spec (Sauber ran an earlier 2016 spec) power unit had a distinct smell to the exhaust gasses. Akin to raw paraffin, the strong smell was always apparent when the Ferrari passed in the pitlane. This year the same smell continues, but with less of a raw eye-watering odour. This smell could be to do with the Shell bio-content in the fuel, but changes to other teams exhaust fumes may be for other reasons. The change in rules means that the engine must vent directly out the back of the car and not into the airbox. This has several effects, it’s one way to prevent oil-burning, it will deposit oil onto the following car and lastly the smell of hot oil is ever present behind every car. For the Ferrari powered cars in the cold Barcelona pitlane, this meant the vented gasses condensed and visible trails of oily smoke emerged from the breather on the right rear of the car.
Having already tested a different diffuser philosophy at Abu Dhabi last year, the rear end of the SF71H takes similar cues for its design as well as a new trick too. The outer edges of the diffuser used to be slanted with a feathered vane set up over recent years. This trades diffuser volume for the beneficial effect of the feather vanes working the diffuser's side vortices. But the new format followed most other teams with squared off corners that makes the diffuser fill its maximum volume.
The rounded panels can be seen either side of the tail light structure, the squared-off outer corners of the diffuser are also evident
There is then the dip in the middle of the diffuser, this boat-tail shape is where the stepped underfloor sweeps up to meet the rest of the diffuser. Teams direct airflow around the sidepods into the boat tail to drive the taller gurney flaps allowed in the middle of the diffuser. Already Ferrari added various flaps and vanes guide airflow, but the new car has a coved bodypanel to enclose the boat tail against the gearbox/crash structure. This prevents the pressure building up in the boat tail from spilling upwards over the wide sections of the diffuser.
Also, with a launch spec car, Red Bull had a slightly less straightforward test, but none the less raised no cause for concern and the general pace and reliability was obviously there.
Curiously running without the X-vane running along the sidepod on the first day, otherwise the car did see key changes, such as a derivative of the older 2017-spec front wing being tried on the last day.
With its jelly-mould sidepods and their tiny high positioned inlet, its been curious to see how Red Bull has arranged its cooling package. Following on from last season, which itself took inspiration from sister-team Toro Rosso, the cooling is split into three areas, the left and right sidepods and the top bodywork, which has become effectively a third sidepod.
Each sidepod houses an intercooler for the turbocharger, then there is only space for a smaller water radiator. The roll hoop inlet, while small and rounded is the inlet for the rest of the cars cooling and breathing needs. The inlet splits horizontally internally into three, the upper inlet feeds a large water radiator for the hybrid system mounted behind the engine, the middle inlet feeds the engine’s airbox and the lower inlet splits left and right to duct air to the oil coolers mounted either side of the engine. This places a lot of weight high up over the engine and makes access to the engine being surrounded by coolers somewhat tricky. It has to be the case that the aero benefit of the shaped sidepods pays in, performance for the losses in Centre of Gravity height and slightly bulkier top bodywork.
With its new VJM11 car revealed early on the first day of testing, resplendent in its racier pink livery this year, its clear that the team have gone more for evolution. It has to be remembered Force India are not the richest team in F1 and with that comes a restricted R&D budget with which to develop the car. It was pointed out by Technical Director Andy Green that the cost to implement the Halo was £1m, so with that budget eaten up, other more involved design ideas had to be shelved, the high-top sidepods being one of them.
Budgets notwithstanding, the car is well thought out, the bargeboard treatment being quite intricate and this continuing the theme of increasing complexity through the car’s aero surfaces. This being typified by the mirror mountings. As explained before the mirrors and their mountings are small area of freedom in the rules, allowing the designer some extra surfaces with which to shape the airflow. In Force India’s case they have the mirror pod mounted by no less than three elements, which is overkill to support a lightweight carbon fibre pod and plastic mirror but does give some small aero performance gain.
It’s now clear that the poor-quality renders released at the teams ‘season’ launch were devoid of a lot of details from the real car. One of the more interesting features among the newly revealed parts, are the strakes along the chassis edge. Similar devices have been added in the past and these have been largely there to meet regulatory dimensions, but such rules have been tidied up and the FW41 does not need such add-ons. Instead the team’s Technical Director, Paddy Lowe confirmed that these were aero devices to aid flow around the cockpit and Halo.
Also, during the test Lowe confirmed the gearbox was still an aluminium casing. It was speculated in the car’s launch analysis, that the casing might have moved to a carbon outer case, but this isn’t the plan this year. Instead the aluminium case will remain for at least 2018, Lowe adding “a carbon case isn’t necessary to be competitive in F1”, while the pressures of weight saving to get down to the minimum weight limit, may be aided by the structural efficiency of carbon. An aluminium case is certainly possible to be either as light or strong as a carbon case, but not both. Its noteworthy that aluminium loses strength at higher temperatures, remembering also that the gearcase houses not only the hot gear cluster, but also the exhaust turbine for the turbocharger. Williams have had a number of inboard suspension failures over recent years, other F1 designers have speculated that they and other handling issues suffered by Williams, are attributable to the aluminium case. As Williams remain the only team to run a metal casing, with Renault being the only other team up until this year, albeit they ran a stronger titanium case.
A tiny detail, that may have relevance to those into the funnier side of street car modifying is the winglet above the tail light. Looking like the comedy mini wing available off the internet, Williams have added a winglet rather than the peak-style capping over the tail light!
As with Force India its traditional for Toro Rosso to simply present its car on the morning of the first test. Thus, it was again this year, the neat STR12 was pushed out to the awaiting press. It was not perhaps the radical departure in looks expected from the design team, independent of its parent team Red Bull. But the team’s job this year was to get the Honda partnership working, so the focus clearly appears to have been on that side and not making huge visible changes. Although one obvious change to back to a wide nose with a thumb-tip, moving away from the slim design that Mercedes also ran last year.
Looking at its new partner Honda, it’s been hard to predict their competitiveness in F1 since they returned in 2015. After three disastrous years with McLaren, when even getting the engine to fit the chassis, let alone run and be competitive was a problem, the outlook for the smaller Toro Rosso team was bleak for 2018. However, the result so far has been quite the revelation. Through out testing the car has been reliable and reasonably fast, eventually completing the most mileage of any team! While rumours of the Honda engine being a detuned 2017 unit, there’s clearly evidence its not the same specification as used in Abu Dhabi at the end of last year.
In the pits the engine note is different, a distinct almost two-stroke style ‘brap’ to the throttle being blipped, then in corners on the overrun or part throttle, the cylinder cutting creating the mis-firing sound is gone. So, while perhaps the hardware may not be much changed, the way the engine is operated is certainly different.
There’s always great detailing on the Toro Rosso cars, while this does not always necessarily lead on to competitiveness, their car always throws up some new ideas. One feature is the Halo bodywork. Remembering that the Halo itself is a titanium tube structure underneath, the visible aspect is all bodywork and teams have stretched the 20mm area around the inner Halo for aerodynamic gain. Toro have a wraparound faring, the top edge featuring a boomerang winglet to direct air down towards the roll hoop inlet but have added another wing below this. Under the Halo there is a narrow span inverted winglet. This works with the upper wing to create a downwash and is unique in F1 so far.
Renault’s launch was with a mix of computer renders and a modified car, clearly showing little variation from the RS17, the team soon admitted the actual RS18 was to be different from the launch imagery. In layout and structure, the actual RS18 isn’t that different, but the aero details have changed showing some curious features, but still not too far from the place-holder bodywork seen before. The bargeboards, vanes around the sidepod and floor slots were all slightly different. While the pylons that hold the front wing on gained McLaren (and now Ferrari) style vanes\slots. Like Williams Renault have added a distinct edge to the side of the chassis ahead of the cockpit for straightening the airflow around the halo\cockpit. These all being details differing only in a small way from the initial spec.
It was clear that the roll hoop inlet had changed slightly to accommodate the Halo, the already wide inlet from 2017 being made wider and shallower to keep it up in the clear air passing over the Halo. But the black bodywork and misleading renders did not show what was below it. Renault has a very tall roll structure above the monocoque, this forms not only the high wide inlet, but another one beneath it. This lower inlet is for the engine’s airbox, being a turbo, the engine literally sucks air in, so the lower position is less affected by the airflow disrupted by the halo. The upper inlets being used to feed coolers mounted behind the engine. The airbox inlet still needs help to get a good filling of air, so Renault have been clever and applied two tricks. Firstly, there is a spoiler fitted between the cockpit headrest and upper inlet, this directs air into the inlet. Then the driver’s helmets have custom crown spoilers to merge the airflow off the helmet over the headrest and into the inlet. All drivers wear Schuberth helmets who no doubt supported this development.
More lateral thinking was applied at the rear of the car. Without the larger T-wings and Monkey wings, the top rear wing could suffer separation on its under surface at high angles of attack. To help support the clean airflow under the rear wing, the exhaust has been repositioned. Most teams run the exhaust as low and flat as the rules allow. Renault have lifted and angled the exhaust tailpipe upwards. This places it in closer proximity to the wing’s under surface, the flow from the tail pipe acts like the monkey seat to keep the flow attached. The wing has been covered with heat resistant coating to protect the inner carbon fibre from the exhausts heat.
Making a similar developmental step to Williams, Haas have had a big shift in design from 2017, although taking the Ferrari mechanical package, the team runs its own aero programme independent of Ferrari. In the second half of 2017 the team started to make bigger steps with the bodywork on the VF17 and this increase in understanding is evident on the VF18. This is apparent in the front wing, bargeboards and the X-vanes along the sidepods, which are feathered into four separate surfaces.
Independent thinking also sticks out with the Halo fairing treatment, while other teams used boomerang wings to shape the airflow, Haas use a series of teeth acting as vortex generators. Similar teeth are used under the middle of the diffuser. Each shark tooth creates a vortex that together combine to pull the airflow down away from the roll hoop inlet. But these teeth are not only fitted above the Halo, but underneath as well, making this only one of two teams to have aero devices under the halo (see Toro Rosso). Also aiding the airflow around the cockpit, the screen on the front rim of the cockpit is made of two parts, left and right and these are quite tall and serrated in design. This will break up the airflow and reduce the buffeting suffered by the driver at speed.
Running the Ferrari power unit, the Haas also runs some of the same cooling arrangement, the radiators in the sidepods are in a “V” shape, this being a longstanding solution for Haas and not related to the high-top sidepod inlet. Behind the engine sits a large water radiator, in the case of Haas this is several cores welded together to form a compact single cooler for the hybrid system.
Continuing to be an enigma in its preparation this years, McLaren had a troubled test, but came out with good pace and mileage despite teething troubles.
Problems started on the morning of Day1 when the car speared off the track with the right rear wheel flying off. The hub failed where the wheel nut fastens on, the entire wheel nut, retention mechanism and part of the hub was intact and recovered from the accident scene. The errant wheel was recovered some way from the stricken car, reminding us all that in the first year of the halo, even with extra wheel tethers and nut fastening mechanisms, wheels and large debris can still be loose on track.
Further issues manifested themselves with an exhaust coupling failure, the connection between the turbo outlet pipe and the main tailpipe leaked and burnt the bodywork. Subsequently further hot spots were discovered with the Renault turbo mounted inside the gearbox casing, requiring extra cooling slots and judicious use of fans and air lines to keep things cool when the car turns to the pits. These issues being part and parcel of new car development and not a sign of larger cooling issues.
In fact, the cooling of the McLaren Renault is one of the car’s unique features. As explained with many of the other cars the cooling package is split between the sidepods and roll hoop. For McLaren this isn’t the case. Perhaps concerned about airflow for the roll hoop inlet with the halo, the roll hoop inlet has been reduced to a minimum and given a singular purpose, feeding the turbo airbox. So, from the roll hoop inlet a single duct feeds back to the air filter and the down to the rear mounted turbo. No radiators or other cooling devices are mounted above or behind the engine. Instead the complete cooling package is housed within the sidepods. This partially explains their conventional inlets and long swept shape, needing to package more coolers and more space to vent their heat. This set up also usefully lowers the car’s centre of gravity and should give McLaren space to create a very narrow sharp topped shark fin for extra effect in turns.
Like Mercedes McLaren have already started running a Monkey seat winglet over the exhaust and attached to the rear wing mount.
Whilst not a leading team and not likely to be in 2018, Sauber have none the less come out with an aggressive car design and one that bears closer scrutiny than perhaps is performance demands. Under the technical directorship of Jorg Zander the design teams have thrown every idea at the car for this year and this shows a lot of ideas that may well be considered by other teams.
Most apparent is the direction Sauber have taken with the sidepods and roll hoop. Already last year Sauber raced a blade type roll structure, rather than a “U” shaped hoop, the structure is a pillar-like design, then inlets are bonded-on as bodywork to the sides of the inner structure. This format is retained in an even more extreme way this year, then the sidepod inlets are very different too. Not changing the side impact structure, Sauber have achieved a sort of high top sidepod inlet from a conventional chassis structure.
There is still a mid-placed inlet, then another smaller inlet placed above the normal sidepod surface next to the chassis. Initially I speculated this upper inlet may serve to feed the turbo airbox, which is a legal and plausible solution. But having now seen the radiator package I can confirm the inlet is for cooling but with a unique radiator arrangement.
Firstly, the roll structure inlets, the semi-circular upper inlet feeds the hybrid system cooler behind the engine, this being a tall triangular shaped panel. The lower inlets on the roll-blade merge and feed the turbo airbox above the engine. Whilst the main sidepod inlets feed the water and auxiliary radiators for the power unit. So, the mysterious upper inlets feed separate ducts that lead to narrow oil coolers stacked above the conventionally placed water radiators. This double decker radiator arrangement is quite unique to F1 and creates a narrow sidepod that achieves the cooling target and still sends a strong airflow around the sidepods towards the diffuser.
More imagination has been applied to the front suspension. Sauber have repackaged the entire suspension, with the inboard spring\damper arrangement now being a typical F1 set up. High mounted rockers operate torsion bar springs and a complex heave element. Also, an anti-roll bar is formed with two interlocking blades in front of the rockers. Then, the upper and lower wishbones are mounted high up, with the top outer pivot created outside of the wheel (Mercedes\Toro Rosso style) to raise the lower wishbone for better aerodynamic performance.
These packaging solutions aren’t new, but there is an aero detail on the top wishbone that is new, small vanes are formed into the wishbone cross section near the front wheel. For many years strict rules have been applied to suspension arms, to prevent them becoming wings or excessively streamlined. Their profile must be symmetrical, and they cannot be angled more 10-deg from horizontal. Sauber have met the symmetrical rule, as each vane is shaped in that way, its merely the profile goes from the basic wishbone-leg cross section to the vane shape. This is a stretch of, but within the rules. Having vanes in this area helps offset the wake of the tyre upsetting the rear bodywork, useful as no other bodywork can be fitted this far up around the front tyre.
Lastly most cars employ an S-duct in the nose. This was originally a Sauber idea since copied by all the teams in the intervening years. The S-duct takes air from under the nose, then ducts it out over the top of the chassis. This has several effects, the primary one being the effect under the nose, reducing the boundary layer effect and improving flow under the raised part of the chassis. It also can help narrow the nose cross section and reduce airflow separation over the top of the chassis. Its gets its name, as the front facing inlet needs to twist in an S-shape to exit rearwards over the chassis. Sauber’s 2018 version uses a particularly large and forward mounted inlet, jutting from under the under nose.